Nahr al-Allan orWadi al-Allan is a river in southernSyria which traditionally marks the natural boundary between theHauran plain and theGolan Heights (though this boundary is alternatively placed atNahr al-Ruqqad instead).[1][2] The Allan is one of the tributaries of theYarmuk, which marks part of the national border of Syria andJordan.
The length of the Allan is about 19 kilometers (12 mi).[3]
The river flows southward from the foot of theTell al-Hara mound (the highest point in the Hauran plain) through the stony, volcanic cone-covered country where the river has an altitude of approximately 440 meters (1,440 ft) above sea level. Here it is slightly lower than the roughly parallel Ruqqad river 5.5 kilometers (3.4 mi) to the Allan's west. The river's altitude declines to about 410 meters (1,350 ft) after it passes near the ruins of Beit Akkar then drops another 18 meters (59 ft) down a cliff. The river becomes narrow at this point and is joined by a ravine called the Wadi Beit Akkar.[4]
After about 0.8 kilometers (0.50 mi) the river again falls about 18 meters (59 ft) over a cliff. A little beyond this point it is joined by the stream historically known as Wadi Jabala.[5] The 'Wadi Jabala' no longer appears on modern maps but it is an ancient toponym named after theGhassanid phylarchJabala ibn al-Harith.[6] Around 2 miles (3.2 km) after the Allan passesHayt it is joined byNahr al-Harir (or Ehreir) and after a further 2 miles (3.2 km) the joint river terminates at the Yarmuk at an elevation of 55 meters (180 ft) above sea level.[7]
32°43′20″N35°53′55″E / 32.7222°N 35.8987°E /32.7222; 35.8987